Construction of towers for support of various items has been practiced for many years. Various towers of various materials, including wood, steel, and, more recently, concrete, have been provided to support, for example, electrical transmission lines. In like manner, wind driven apparatus including windmills and wind-driven power generators in various forms and designed for many purposes (including, for example, pumping of water from wells as well as, more recently, generation of electrical power) have also been developed.
Various systems and methods are known in the tower construction and support arts for erecting tower structures. For example, U.S. Pat. No. 3,945,107 to Houck discloses a process for erecting a vertical rising mast. U.S. Pat. No. 6,614,125 to Willis et al. discloses a method and means for mounting a wind turbine on a tower. U.S. Pat. No. 7,877,934 to Livingston et al. discloses a lifting system and apparatus for constructing wind turbine towers. U.S. Pat. Appl. Pub. No. 2010/0281819 to Thompson discloses a slip formed concrete wind turbine tower. Further examples of erection methods and apparatus are disclosed in Zavitz et al. (U.S. Pat. App. Pub. No. 2009/0307998), Zavitz et al. (U.S. Pat. App. Pub. No. 2009/0308006), and Knox et al. (U.S. Pat. App. Pub. No. 2009/0308019).
The subject matter of each of the above-referenced published patent-related documents is fully incorporated herein by reference, and for all purposes.
Many known systems and methods for erecting tower structures are slow and cumbersome, requiring, for example, numerous external cranes or other machinery to lift and position the various elements of the tower structures relative to each other. Additionally, as tower structures increase in size and height, available cranes and other machinery may not be capable of placing various elements of the tower structures at their required heights. For example, presently known cranes may not be capable of hoisting tower elements above heights of approximately 75 meters. However, some tower structures may require elements that are disposed at 120 meters, or higher. Further, the forces required to lift the various elements of a tower structure utilizing currently known systems and methods may be relatively high, due to the weight of the elements and the heights to which the elements must be hoisted.
Thus, system and method subject matter for erecting a tower structure that is relatively fast and efficient would be desired in the art. Additionally, system and method subject matter for erecting a tower structure that allows elements of the tower structure to be placed at relatively high heights would be advantageous. Further, system and method subject matter for erecting a tower structure that does not require large forces to lift the various elements of the tower structure relative to each other would be desirable.